You have a great question as there is often a large amount of time between when the investment is made and when the I-526 is approved, and all of the jobs can be created well before an approval! Generally, as long as the jobs are created when filing the I-829 to remove the conditions, the jobs can be created at any time as long as they are as a result of the investment.
There is an acceptable timeline but each project may dictate its own timeline .For instance, jobs may be created before the EB-5 funds are committed to the project. Also the required jobs must have occurred before the I-829 is adjudicated.